With shrinking dimensions of various integrated circuit components, transistors such as field-effect transistors (FETs) have experienced, over time, dramatic improvement in both performance and power consumption. These improvements may be largely attributed to the reduction in dimensions of components used therein, which in general translate into reduced capacitance, resistance, and increased through-put current from the transistors. Nevertheless, performance improvement brought up by this type of “classic” scaling, in device dimensions, has recently met obstacles and in some cases even been challenged, when the scaling goes beyond a certain point, by the increase in leakage current and variability that are inevitably associated with this continued reduction in device dimensions.
In general, power consumption and performance of integrated circuits stem from and depend upon capacitance, resistance, and leakage current of components, such as electrical junctions, wires, property of dielectric material, etc., that the integrated circuits may contain. In the case of a field-effect-transistor, it has been discovered that capacitance in the drain side and resistance in the source side, in particular, contribute largely to the overall performance of the FET, and reductions in capacitance in the drain side and resistance in the source side may help further improve performance of the FET.